Low Water Pressure: Causes and Fixes for Austin Homes

When your shower feels like a weak drizzle, here's what's probably going on—and what to do about it.

I'm Justin Sims, and low water pressure is one of those problems that starts as a minor annoyance and slowly drives you crazy. That pathetic trickle from your showerhead, the faucet that takes forever to fill a pot, the sprinkler system that barely reaches the lawn—it all adds up to a frustrating daily experience.

The good news? Most water pressure problems have identifiable causes and fixable solutions. Let me walk you through what's probably happening in your home.

Understanding Water Pressure Basics

Before we troubleshoot, let's talk numbers. Normal residential water pressure runs between 40-60 PSI (pounds per square inch). Below 40 PSI, you'll notice weak flow. Above 80 PSI can actually damage your plumbing and appliances.

If you want to test your water pressure at home, pick up a pressure gauge at any hardware store for about $10. Screw it onto an outdoor hose bib, make sure no water is running inside, and read the gauge. This gives you a baseline for the whole-house supply.

Cause #1: Clogged Aerators and Showerheads

This is the first thing I check, and it solves the problem about 30% of the time.

What's Happening

Aerators are those tiny screens at the end of your faucet. Over time, they collect mineral deposits, sediment, and debris. Same with showerheads. When they clog, water flow drops—even though the pressure behind them is fine.

How to Check

• Unscrew the aerator from the faucet tip (most twist off by hand)
• Look for crusty white or green buildup
• Check if flow improves without the aerator

The Fix

1. Remove aerators and showerheads
2. Soak in white vinegar overnight (or for a few hours)
3. Scrub with an old toothbrush
4. Rinse thoroughly and reinstall

**If the pressure is fine without the aerator, you've found your culprit.** Cleaning or replacing these inexpensive parts often solves the problem completely.

Cause #2: Partially Closed Valves

You'd be surprised how often this is the issue—especially in homes that have had recent work done.

Main Shut-Off Valve

Your main water shut-off valve might not be fully open. This is common after plumbing repairs, or if someone partially closed it and forgot.

**Check:** Find your main valve (usually where the water line enters your home) and make sure it's fully open. For a gate valve, turn it counterclockwise until it stops. For a ball valve, the handle should be parallel to the pipe.

Water Meter Valve

There's also a valve at your water meter near the street. If the city did work recently, they might not have reopened it all the way.

**Check:** This one usually requires a meter key, but you can visually inspect if the valve handle is in the open position.

Fixture Shut-Offs

Each sink, toilet, and appliance has individual shut-off valves. If pressure is low at just one fixture, check that its valves are fully open.

Cause #3: Corroded or Clogged Pipes

This is more common in older Austin homes, especially those built before the 1990s.

Galvanized Steel Pipes

Many older Hill Country homes still have galvanized steel pipes. Over decades, these pipes corrode from the inside, building up layers of rust and mineral deposits that restrict water flow.

Signs:

• Low pressure throughout the house
• Pressure has declined gradually over years
• Brownish water when you first turn on taps
• Home was built before 1990

The Fix

If your home has galvanized pipes and you're experiencing chronic low pressure, repiping is often the long-term solution. It's a significant investment, but it permanently solves the problem and increases home value.

Cause #4: Municipal Supply Issues

Sometimes the problem isn't in your home at all.

How to Check

Ask your neighbors if they're experiencing the same issue. If multiple homes on your street have low pressure, the problem is likely with the municipal supply or a main line issue.

What to Do

• Contact Austin Water (or your water provider) to report the issue
• Ask if there's scheduled maintenance or a known problem
• Request a pressure test at the meter

**Note for Well Water Homes:** If you're on well water, pressure issues might indicate a failing pressure tank or well pump. These require professional diagnosis.

Cause #5: Pressure Regulator Failure

Many homes have a pressure-reducing valve (PRV) where the main line enters the house. It protects your plumbing from excessively high municipal pressure.

When They Fail

PRVs can fail in two ways:

• **Stuck closed or partially closed:** Results in low pressure
• **Stuck open:** Results in dangerously high pressure

Signs of PRV Failure

• Sudden pressure change (not gradual)
• Pressure is different on different floors
• PRV looks corroded or is leaking
• PRV is more than 10-15 years old

The Fix

PRV replacement is a straightforward repair for a licensed plumber. They typically last 10-15 years and cost a few hundred dollars to replace.

Cause #6: Peak Usage Times

If your pressure drops at certain times of day, you might be experiencing peak demand issues.

What's Happening

When everyone in the neighborhood waters their lawn, fills their pool, or showers in the morning, municipal supply gets stretched thin.

Signs

• Pressure is fine at 2 AM, weak at 7 AM
• Worse on weekends when everyone is home
• Worse in summer during lawn watering season

What to Do

• Time your high-water activities for off-peak hours
• Consider a pressure booster pump if the problem is severe
• Talk to your water provider—sometimes they can adjust your service

Cause #7: Leaks Stealing Your Pressure

A significant leak somewhere in your system can reduce pressure throughout the house.

Signs of Hidden Leaks

• Water bill suddenly increased
• Wet spots in yard (could be service line leak)
• Sound of running water when nothing is on
• Water meter dial spinning when no water is being used

How to Check

Turn off all water in your home. Go to your water meter and watch the flow indicator (usually a small triangle or dial). If it's moving, you have a leak somewhere.

The Fix

Leak detection and repair. This could be anything from a dripping pipe in the wall to a cracked service line under your yard.

Cause #8: Water Heater Issues

If low pressure only affects hot water, your water heater might be the problem.

What to Check

• **Inlet valve:** Make sure it's fully open
• **Sediment buildup:** Accumulated sediment can restrict flow
• **Crossover:** A failed mixing valve can cause pressure imbalances

The Fix

Annual water heater flushing helps prevent sediment buildup. If pressure is significantly worse on hot versus cold, have the water heater inspected.

Quick Diagnostic Checklist

Low pressure at one fixture:

→ Clean or replace aerator/showerhead

→ Check fixture shut-off valves

Low pressure at multiple fixtures: